Article slugs

app/controllers/admin/articles_controller.rb

@@ -47,7 +47,7 @@ def destroy
     private
 
     def find_article
-      @article = Article.find(params[:id])
+      @article = Article[params[:id]]
     end
   end
 end

app/controllers/articles_controller.rb

@@ -1,5 +1,6 @@
 class ArticlesController < ApplicationController
   before_filter :find_article, :only => [:show, :edit, :update, :share]
+  before_filter :redirect_to_slug, :only => [:show]
   before_filter :create_visit, :only => [:show]
 
   skip_before_filter :authenticate,      :only => [:shared, :samples]
@@ -80,11 +81,7 @@ def random
   private
 
   def find_article
-    if params[:volume] && params[:issue]
-      @article = Article.find_by_issue_number("#{params[:volume]}.#{params[:issue]}")
-    else
-      @article = Article.find_by_id(params[:id])
-    end
+    @article = Article[params[:id]]
 
     render_http_error(404) unless @article
   end
@@ -108,4 +105,9 @@ def create_visit
     end
   end
 
+  def redirect_to_slug
+    return unless @article.slug.present?
+
+    redirect_to article_path(@article.slug) unless params[:id] == @article.slug
+  end
 end

app/models/article.rb

@@ -3,7 +3,8 @@ class Article < ActiveRecord::Base
   belongs_to :volume
   belongs_to :collection
 
-  validates_presence_of :issue_number
+  validates_presence_of   :issue_number
+  validates_uniqueness_of :slug, :allow_blank => true
 
   def self.in_volume(number)
     includes(:volume)
@@ -18,6 +19,18 @@ def self.drafts
     where(:status => "draft")
   end
 
+  def self.[](key)
+    find_by_slug(key) || find_by_id(key)
+  end
+
+  def to_param
+    if slug.present?
+      slug
+    else
+      id.to_s
+    end
+  end
+
   def full_subject
     "Issue #{issue_number}: #{subject}"
   end

app/views/admin/articles/_form.html.haml

@@ -4,6 +4,10 @@
   = f.label :subject
   %br
   = f.text_field :subject
+%p
+  = f.label :slug
+  %br
+  = f.text_field :slug
 %p
   = f.label :published_time
   = f.date_select :published_time

db/migrate/20130816174433_add_slug_to_articles.rb

@@ -0,0 +1,5 @@
+class AddSlugToArticles < ActiveRecord::Migration
+  def change
+    add_column :articles, :slug, :string
+  end
+end

db/schema.rb

@@ -11,7 +11,7 @@
 #
 # It's strongly recommended to check this file into your version control system.
 
-ActiveRecord::Schema.define(:version => 20130215174537) do
+ActiveRecord::Schema.define(:version => 20130816174433) do
 
   create_table "announcements", :force => true do |t|
     t.text     "title"
@@ -43,6 +43,7 @@
     t.text     "issue_number"
     t.integer  "volume_id"
     t.integer  "collection_id"
+    t.string   "slug"
   end
 
   create_table "authorization_links", :force => true do |t|

test/integration/article_routing_test.rb

@@ -0,0 +1,35 @@
+require_relative "../test_helper"
+
+class ArticleRoutingTest < ActionDispatch::IntegrationTest
+  setup do
+    @article = FactoryGirl.create(:article, :slug => "awesome-article")
+    simulated_user { register Support::SimulatedUser.default }
+  end
+
+  test "by slug" do
+    visit "/articles/awesome-article"
+
+    assert_content @article.subject
+  end
+
+  test "by id" do
+    id = @article.id
+    visit "/articles/#{id}"
+
+    assert_content @article.subject
+
+    assert_current_path "/articles/awesome-article"
+  end
+
+  test "with invalid slug" do
+    visit "/articles/i-do-no-exist"
+
+    assert_equal 404, page.status_code
+  end
+
+  test "with invalid id" do
+    visit "/articles/99999"
+
+    assert_equal 404, page.status_code
+  end
+end

test/integration/edit_article_test.rb

@@ -0,0 +1,27 @@
+require_relative '../test_helper'
+
+class EditArticleTest < ActionDispatch::IntegrationTest
+  setup do
+    simulated_user { register Support::SimulatedUser.default }
+    @article = FactoryGirl.create(:article, :slug => "awesome-article")
+    User.first.update_attribute(:admin, true)
+  end
+
+  test "can edit articles with slugs" do
+    visit edit_admin_article_path(@article.slug)
+
+    click_button "Update Article"
+
+    assert_current_path article_path(@article)
+  end
+
+  test "can edit articles without slugs" do
+    @article.update_attribute(:slug, nil)
+
+    visit edit_admin_article_path(@article.id)
+
+    click_button "Update Article"
+
+    assert_current_path article_path(@article)
+  end
+end